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Modular pyridine synthesis from oximes and enals through synergistic copper/iminium catalysis.

Journal of the American Chemical Society (2013-02-27)
Ye Wei, Naohiko Yoshikai
ABSTRACT

We describe here a [3+3]-type condensation reaction of O-acetyl ketoximes and α,β-unsaturated aldehydes that is synergistically catalyzed by a copper(I) salt and a secondary ammonium salt (or amine). This redox-neutral reaction allows modular synthesis of a variety of substituted pyridines under mild conditions with tolerance of a broad range of functional groups. The reaction is driven by a merger of iminium catalysis and redox activity of the copper catalyst, which would initially reduce the oxime N-O bond to generate a nucleophilic copper(II) enamide and later oxidize a dihydropyridine intermediate to the pyridine product.

MATERIALS
Product Number
Brand
Product Description

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